White gold
from the Antique Jewelry University
White gold was invented in the 19th century where it was alloyed with palladium. It became commercially available as of 1912 in Pforzheim, Germany and gained popularity in the mid-1920's as a low cost substitute for platinum. It is an alloy of gold with copper, zinc and nickel. In more recent times the nickel in this alloy has often been replaced by a platinum family metal due to allergic reactions.